Dispensing cylinder, large capacity dispensing device and method of using large capacity dispensing device

A dispensing cylinder comprising:

• a small diameter section, a large diameter section which communicates with said small diameter section and is capable of holding fluids, a sliding section provided in a slidable manner within said large diameter section which enables fluid to be sucked and discharged to and from said large diameter section through said small diameter section, and a connection section which connects said sliding section in a detachable manner to a suction and discharge mechanism which drives said sliding section;
• wherein the sliding section comprises:
• a disk-shaped piston which slides inside the large diameter section;
• a rod, one end of which is secured to the piston, wherein the connection section is provided at the other end of the rod;
• and
• a tube supported by an end of the large diameter section that axially opposes the small diameter section, the tube having a diameter and being positioned, relative to the rod, such that:
• the rod passes through the inside of the tube,
• relative axial movement between the rod and the tube is permitted,
• the rod is substantially axially aligned with the large diameter section at the end of the large diameter section that axially opposes the small diameter section, and
• the tube is axially positioned between the piston and the connection section and thereby prevents the piston from exiting the large diameter section through the end of the large diameter section that axially opposes the small diameter section.